You have wind and I have sun – shall we trade?

May 10, 2017

Very few people stop to consider where their electricity comes from. It is simply something that is there and which we pay for every time we receive our quarterly electricity bill. But just as more and more people want to buy their vegetables from a local farmer, so too will we see a growing desire to have a say in how our electricity is produced—and consequently to create our own power grid within a small local area. This is very much the thinking of Professor Pierre Pinson from DTU Electrical Engineering, who is currently developing a model for such a local electricity system.

In Denmark, it is illegal to sell electricity to your neighbour outside of the central power grid. Any surplus electricity from solar cells on the roof, for example, must be returned to a power station. However, this is something that Pierre would like to change with his project ‘5s’ – Future Electricity Markets’:

“We’ve almost got 50 per cent wind energy in the system with a minimum of local commitment. If you let people take charge of their energy purchases, they will become more aware of where the energy comes from and then we might even achieve higher levels. This project aims to challenge the established rules. We hope that we can create a popular movement for a sharing economy within the power sector.”

Barter
Pierre is working on several small network models: Should the local neighbour network be disconnected from the central grid? Can we envisage a model whereby each member can freely choose an energy supplier anywhere in the country? And what about payment?

A working model will be generated by the Svalin co-housing complex in Roskilde, Denmark. Here, 50 families live in houses with solar cells and heat pumps which are so efficient that the houses are not only energy-neutral, but also generate an energy surplus the residents want to share.

Some may have an electric car they want to charge exclusively using solar energy, while others may want to channel solar energy from a house standing empty during the day to one where the residents are at home during the daytime. In order to manage this energy exchange, Pierre will initially install a measurement system that provides a clear picture of actual energy consumption. He then expects that minicomputers in each house will manage the energy exchange based on price algorithms that measure in kWh, as the residents of Svalin from the outset have said that they do not want money involved.
They would rather pay in kind in the form of a beer at the Friday bar, help with childminding, etc. And Pierre has taken their feedback on board—for as he says—the cost of energy is nearing zero.

“If you can produce solar energy from your roof, then it is basically cost-free. The cost of installations is currently falling dramatically. The biggest cost will be setting up the system,” he says, adding that users will probably want to supplement it with a connection to the central power grid to ensure that the necessary energy is always available.

Some have objected to the system, claiming that it is just a way of getting out of paying tax, which Pierre finds unfortunate.

“Buying energy from your neighbour—or generally trying to solve problems within the small community framework and being more responsible for its energy consumption—is so much more than a means of circumventing taxes,” he says, pointing out that it will not be a problem registering how much energy each individual household uses and deducting tax based on consumption. He is convinced that sooner or later, shared economy will gain traction in the energy sector—and here, Denmark must lead the way.